Someone mentioned there's no way to cancel from the link we include in this email (https://plausible.io/billing/upgrade) so I'm changing it to the settings page instead https://plausible.io/settings. My own https://plausible.io/billing/upgrade is a bit different than normal subscribers see it so I don't actually know if there's a way to cancel on it. If there is a way there too, feel free to ignore this
* Add background job to send renewal notification
* Use copy from Marko
* Add expiration email in case the user has cancelled
* Add queue config
* Use correct tag for expiration email
